UDP发送和接收程序
1、receive[cpp]
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#define BUF_SIZE 512
int create_udp_socket(char *ip, int port){
int onOff = 1;
struct sockaddr_in addr;
addr.sin_family = AF_INET;
addr.sin_addr.s_addr = inet_addr(ip);
//addr.sin_addr.s_addr = htonl(INADDR_ANY);
addr.sin_port = htons(port);
int sockfd;
if ((sockfd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1) {
return(-1);
}
fcntl(sockfd, F_SETFD, FD_CLOEXEC);
setsockopt(sockfd,SOL_SOCKET, SO_REUSEADDR, (const void *)&onOff, sizeof(onOff));
if (bind(sockfd, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
close(sockfd);
return(-1);
}
return sockfd;
}
void listen_udp(int socket){
socklen_t sin_len;
char msg_buffer[BUF_SIZE];
struct sockaddr_in sin;
sin_len=sizeof(sin);
fd_set rfds;
struct timeval tv;
int retval;
int rlen = 0;
int socket_descriptor;
socket_descriptor = socket;
while(1){
FD_ZERO(&rfds);
FD_SET(socket_descriptor, &rfds);
tv.tv_sec = 4;
tv.tv_usec = 0;
retval = select(socket_descriptor+1, &rfds, NULL, NULL, &tv);
if (retval == -1){
printf("select error %d %s\n",socket_descriptor,strerror(errno));
break;
}
else if (retval){
memset(msg_buffer, 0, BUF_SIZE);
if(FD_ISSET(socket_descriptor, &rfds)){
rlen = recvfrom(socket_descriptor, msg_buffer, BUF_SIZE, 0, (struct sockaddr *)&sin, &sin_len);
if(rlen > 0){
printf("recv %s \n", msg_buffer);
}
else{
printf("rlen : %d\n", rlen);
}
}
}
}
close(socket_descriptor);
}
void main(void){
int socket;
socket = create_udp_socket("127.0.0.1",1000);
listen_udp(socket);
}
2、send
[cpp]
#include"common.h"
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
int send_message_to_player( const char* ip_address, const unsigned int port, char *info )
{
struct sockaddr_in servaddr;
int sockfd;
if (!ip_address) {
return 1;
}
sockfd = socket(AF_INET,SOCK_DGRAM, 0);
if (sockfd < 0) {
printf("error opening socket");
return 1;
}
memset(&servaddr, 0, sizeof(servaddr));
servaddr.sin_family = AF_INET;
servaddr.sin_addr.s_addr = inet_addr(ip_address);
servaddr.sin_port=htons(port);
sendto(sockfd, info, strlen(info), 0,
(struct sockaddr *)&servaddr, sizeof(servaddr));
close(sockfd); www.zzzyk.com
return 0;
}
void main(void)
{
char buf[]="<info title=\"test\"><status>1</status><message>12345</message><info>";
send_message_to_player("127.0.0.1",1000,buf);
}
补充：软件开发 , C++ ,
